If North Korea attacked South Korea, the communist state would be defeated and the two Koreas would be reunified eventually, the commander of the Eighth U.S. Army here said.

``There is no doubt, if the North Koreans decide to cause trouble, what the outcome will be. No doubt at all,'' Lt. Gen. Joseph Fil Jr. was quoted by the Stars and Stripes as saying.

The remarks, made during an orientation Friday for U.S. Department of Defense Dependents Schools teachers new to South Korea, came ahead of the start of a large-scale computerized joint military exercise by South Korean and U.S. troops Monday.

The five-day Ulchi Freedom Guardian is aimed at evaluating and improving interoperability between the two forces. South Korea leads this year's exercise, formerly known as Ulchi Focus Lens, for the first time to prepare for its takeover of wartime operational control of its troops from the U.S. military in 2012.

To that end, the two sides are to run separate operational commands led by Gen. Kim Tae-young, chairman of South Korea's Joint Chiefs of Staff (JCS) and Gen. Walter Sharp, commander of the U.S. Forces Korea. Sharp concurrently serves as chief of the Korea-U.S. Combined Forces Command and the United Nations Command.

About 56,000 South Korean troops and 10,000 American troops will take part in the command and control, war-fighting exercise, according to the JCS.

North Korea regularly denounces joint military drills by South Korea and the United States. It calls the drills a rehearsal for invasion.

The two Koreas remain technically at war, since the 1950-53 Korean War ended in a truce, not a peace treaty.

Fil also said there would be no more reduction in the U.S. troop level on the Korean Peninsula.

``In fact, we're going to pick up the force level a bit,'' he said.

U.S. Forces Koreas spokesman David Palmer said the commander was referring to the increased number of family members who will accompany service members to Korea in coming years as tours become normalized.

The U.S. military is looking for a policy to allow more U.S. troops in South Korea to serve for three years and bring their families, instead of serving on one-year unaccompanied tours.

In April, President Lee Myung-bak and U.S. President George W. Bush agreed to pause a drawdown of U.S. soldiers in South Korea, maintaining the number at about 28,000.

That number was scheduled to drop to 25,000 by the end of the year, when the drawdown was scheduled to end. The U.S. and South Korea agreed on this in 2004, when the United States had 38,500 troops stationed in South Korea.